HIV incidence among Black men who have sex with men (BMSM) in the southeastern United States is among the highest in the world. Current trends show that as many as 60% of BMSM will contract HIV by the age of 40 and nearly half (46%) of BMSM who are living with HIV in the US are undiagnosed. Infrequent HIV testing and the poor uptake of evidence-based approaches to preventing HIV by BMSM, particularly HIV pre- exposure prophylaxis (PrEP), constitutes a public health crisis. Among the factors that impede HIV prevention for BMSM, including HIV testing and linkage to PrEP, are the social stigmas and discrimination based on race, sexual orientation and HIV-risk. Furthermore, combinations of stigmas, including race, sexual orientation and HIV-risk intersect to shape unique experiences such that BMSM are stigmatized not just through racism and homophobia, but by the unique experiences of being a Black man who engages in same- sex sexual behaviors. Stigmatized characteristics intersect within individuals, a concept known as intersectional stigma; the juncture of multiple stigmatized characteristics including race, sexual orientation and HIV-risk. However, there are few measures of intersectional stigma and none are designed for use in HIV prevention with BMSM. Reliable and valid measures of internalized, anticipated, and enacted stigmas that encompass the concept of intersectionality are needed to improve HIV prevention intervention research. The proposed research will meet the need for measures of intersectional stigma by developing and testing a novel and parsimonious approach to assessing intersectional internalized, anticipated, and enacted stigmas. This research is grounded in the HIV Stigma Framework and will capitalize on standard computerized interviewing to administer assessments of internalized, anticipated and enacted stigmas attributed at the item-level to multiple personal characteristics (race, sexual orientation, and HIV-risk). Two studies will be conducted to test the reliability and validity of this innovative approach to simultaneously assessing multiple stigma dimensions. Study 1 will perform rigorous psychometric analyses and confirmatory factor analyses to establish the reliability and concurrent validity of the intersectional stigma scales in a sample of 500 BMSM who have not been tested for HIV in the previous 6-months and meet the CDC criteria as a candidate for PrEP but have never been prescribed PrEP. Study 2 will serve to cross-validate scale reliability and concurrent validity and determine the time stability (test-retest reliability) and predictive validity of the intersectional stigma scales in a sample of 300 BMSM meeting the same criteria described above. Participants in Study 2 will be assessed twice over a 4-month period. Regression models will test the predictive validity of the scales, specifically predicting HIV testing, PrEP interest and PrEP uptake over 4-months. Findings from the two-years of research will yield a new approach to measuring intersectional stigma to advance HIV testing, PrEP use, and other prevention interventions targeted to BMSM and other stigmatized groups.